ive got a 2500hd with 05+efans that is overheating sometimes. its fine around town, but when i was on a road trip it was about 105 out and cruising at about 85 mph it would get up to about 235 with the a/c on pulling grades (anytime rpms were up really) i didnt notice this at all last summer. now we just picked up a camper the weighs about 6000 lbs and it will get hot 235-240 when pulling grades and it was only 75 out. i have a larger trans cooler as well and it stays about 125 until engine temp gets hot then it gets up to about 200.

i replaced the thermostat and the temp sensor. water pump is about a year or so old NAPA unit. only thing i can thing of really is maybe the radiator is plugged? or partially? i tow alot in the winter and never overheats but its also below freezing most of the time.

any ideas/suggestions? ive cleaned the fins of the radiator and condenser, deffinatly air traveling through. it will cool down if i pull over and idle for about 5 min but heats back up til im off the grade

 

Sounds like a radiator problem to me, since it's doing it at speed.

It could be internally plugged up if you confirmed that the front is not full of debris/trash (they get like that over time).

The other considering is that your thermostat isn't working properly.

 

ya first thought was thermostat, thats why i replaced it. and it was the original so i figured what the heck. but no dice.

 

Water pump could be bad

 

I have an 05 and every now and then mine runs hot. I popped the hood one day and found only one fan running...it only happens every once in a while though.

 

any luck?

 

After a whole year, I'd hope so lol.

 

I replaced the radiator with an aluminum one that is 1/4" thicker. But ive been deployed til now so ill probably know here soon. I think im going to throw on a flowcooler water pump and 160 tstat as well here soon.

 

its no longer overheating